Sympathetic pain is a type of nerve pain that arises due to abnormalities in the function of the sympathetic nervous system. With sympathetic pain an abnormality in a group of nerves called a ganglion cause pain to an organ or body region. To treat sympathetic pain physicians can block a ganglion with the injection of medication into a specific area of the body. To therapeutically treat acute pain a physician injects a local anesthetic into the affected neuronal ganglion. This type of treatment may be referred to as a nerve block.
The sphenopalatine/pterygopalatine ganglia is a neuronal structure located principally in the center of the head in the pterygopalatine fossa posterior to the middle turbinate. The sphenopalatine/pterygopalatine ganglia comprises the largest cluster of sympathetic neurons in the head outside of the brain. The sphenopalatine/pterygopalatine ganglia interfaces and directs nerve impulses to the majority of the head's autonomic or parasympathetic pathways. Therefore, any abnormality or injury to this structure may cause severe pain. A nerve block of the sphenopalatine/pterygopalatine ganglia is effective in relief in a variety of pain conditions ranging from headache to lower back pain. Additionally, other disease processes such as headache disorders and other neurological conditions can be arrested, or improved by local anesthetic blockade, and/or other pharmacological augmentation or mechanical alteration of the sphenopalatine/pterygopalatine ganglia and surrounding structures.
Unfortunately, because of the anatomical position of the sphenopalatine/pterygopalatine ganglia, the structure is very difficult to block with a local anesthetic solution. The anatomical location of the sphenopalatine/pterygopalatine ganglia is dangerously close to many vital and delicate mid brain structures. Although direct needle placement can be employed under fluoroscopic guidance to administer anesthetic to the sphenopalatine/pterygopalatine ganglia, most practitioners will not attempt the procedure due to the technical difficulty and extreme dangers of an aberrant needle placement.